more interrupts with polling(4) on em(4)

[Gergely CZUCZY]

On Sat, Jul 28, 2007 at 12:52:00AM +0200, Markus Oestreicher wrote:
> Gergely CZUCZY schrieb:
> >Good morning,
> >I've noticed 33K interrupts/sec on an em(4) gigabit interface on
> >a box. This many interrupts seemed a bit too high, so I thought
> >I should enable polling(4). After enabling it i've got 55K per
> >second, even higher.
> >I've just done "ifconfig em1 polling", and by this the number
> >of interrupts increased.
> 
> 
> How does vmstat -i look like before and after?
lvs1:~# ifconfig em0 -polling; sleep 5; vmstat -i ;ifconfig em0 polling; sleep 5; vmstat -i

(without polling on em0)
interrupt                          total       rate
irq14: ata0                           60          0
irq15: ata1                            1          0
irq16: uhci0 twe0                   2507          1
irq17: fxp0                      4922443       1987
irq18: em0                       3302239       1333
cpu0: timer                      4952925       1999
Total                           13180175       5321

(with polling on em0)
interrupt                          total       rate
irq14: ata0                           60          0
irq15: ata1                            1          0
irq16: uhci0 twe0                   2508          1
irq17: fxp0                      4965974       2000
irq18: em0                       3302338       1330
cpu0: timer                      4962989       1999
Total                           13233870       5331

Sincerely,

Gergely Czuczy
mailto: gergely.czuczy at harmless.hu

-- 
Weenies test. Geniuses solve problems that arise.
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